1. Field
The present disclosure relates to a thin-film transistor and a display device having the same, and more particularly, to a thin-film transistor including an oxide semiconductor and a display device having the thin-film transistor.
2. Discussion of the Related Technology
A thin-film transistor includes a semiconductor layer which provides a channel region, a source region and a drain region, a gate electrode which overlaps the channel region and is insulated from the semiconductor layer by a gate insulating layer, and a source electrode and a drain electrode which are connected to the source region and the drain region of the semiconductor layer.
The thin-film transistor structured as described above is applicable not only to semiconductor integrated circuits but also to display devices such as liquid crystal displays (LCDs) and active matrix organic light-emitting diode (AMOLED) displays.
An increase in the resolution and size of a display device leads to a reduction in wiring width and an increase in wiring length, thus causing a sharp increase in wiring resistance. As the wiring resistance increases, an electric current or voltage applied to pixels becomes non-uniform due to a voltage drop (IR drop). This results in a defect or a reduction in image quality. Therefore, wirings such as electrodes of a thin-film transistor, scan lines and data lines are mostly formed of copper (Cu) with low resistivity.
However, if Cu is used for the wirings, device characteristics may deteriorate due to diffusion of the Cu.
Therefore, a thin-film transistor structured to prevent or block diffusion of Cu and ensure superior device characteristics needs to be researched.